Theories on the origin of life
Publication date 1969
Publisher [S. l.] Encyclopaedia Britannica Educational Corp.
Digitizing sponsor Internet Archive
Contributor Internet Archive
Author, Cyril Ponnamperuma
Discusses four theories which explain the origin of life
Ocr Life. Is passed from generation to generation. And with it the quest for the secret that light's origin. This is the story of man's quest for that secret. Among all the living creatures of the earth. Man alone is consciously aware themself as a living being is life is priceless to him. Man knows that without like he is nothing. Is made the discovery of death. Since time unknown years laboured with all his skills to preserve and prolonging the vital spark of life. But what life is and where it came from man does not know. Some men have speculated that life was a gift of the gods. Wonder about life's origins may be as old as the earliest man. Embedded in stone remnants of ancient lie that haunted his imagination and his imagination is linked him to a known generations of the that. Did life perhaps arise somehow from the non-living murder the river coursing through ancient Kenyans. Or was it perhaps blown to from some far corner of the universe. The forms of life's beginnings a phantom hidden some believe in the secrets of an earlier environment from which our own world evolved. How did life begin. Even. At. The dawn of civilization man was ordered by the mystery of being allied to a Pentium of gods. He attributed the Browns a of sun rain and harvest and the disasters of earthquake and storm. To a god also a tribute at the gift of life. He speculated that a supernatural being or power designed the universe and created in it each separate species. This theory of special creation and out with religious authority. But the modern scientist working in his laboratory through observation and experimentation cannot test the theory of special creation. His investigations may lead to an understanding of the conditions required for life sorry gins. Long ago man began to observe the environment in which he lived his observations led him to speculate on a possible source of life. He had seen muddy river is apparently empty of life suddenly swarming with fish. On to Kate organic matter where he had seen nothing maggots appeared. Man speculated that life must arise spontaneously from non-living matter. But did life begin by some kind of spontaneous generation to find out. Man began to look more closely at life to test his theories in laboratory experiments the fish in one flask was covered this in the other flask was left uncovered. On the fish in the open flask flies gathered. Later when the other flask was uncovered. There was no sign of life but on the fish which had not been covered. Maggots appeared did the Flies. Deposit the maggots on the face. Once man had the microscope he could easily see the flies. Eggs from which maggots developed life appeared to have come from life. And they could see a new world of life never before observed. The world of microorganisms. A new question arose where did micro-organisms come from the man who first used microscopes could not always distinguish between living and non-living matter. Therefore some thought that microorganisms generated spontaneously from decayed organic materials. And experiments in the nineteenth century. Louis faster bread fruit in microorganisms in open flasks exposed to the air. But in his other flasks no microorganisms grew their long curve next trapped microorganisms from the air before they could reach the infusion. This tour at initially sterilized both infusions by boiling them. Together further evidence that's to remove the curve neck of one flask exposing the infusion to microorganisms in the air. The neck of the other flask remained in place. Later microorganisms grew in the exposed flask. Pastor and most scientist with him believed he had proved that micro-organisms existed in the air that they did not generate spontaneously. Closer observation and experiment in the laboratory showed that under the conditions of the experiment. Life came from life. But did it. To other men. Fossils suggested a third way in which life might have developed on Earth the strange forms and then to quickly of fossils made them think that life might be eternal. They propose that life at all is existed somewhere in the universe that from other planets living organisms in the form of bacterial spores had been blown to earth through space there to begin the evolution of the earth's living creatures. Proponents of this cousin is all it cleary believe that spores might have come to Earth from meteorites in modern laboratories that Cheerio spores have been subjected to the conditions of the interplanetary journey if you have been found that could survive the radiation intensity of outer space the question remains where and how my life have begun. Elsewhere in the cosmos. The theory that life came from other planets leaves I'm answer the question of what kind of life could have survived such a journey. But what's of that other journey. Biological evolution before man had tested the cousins or like they are in the laboratory he was beginning to explore another idea that might lead to an explanation of life this was Charles Darwin's idea that the living world evolved from lower forms of life. Yet how far back does biological evolution go. Since Darwin is time man is found increasing evidence of lives and take a day. Using modern techniques he has learnt to date the evidence the oldest fossils have been dated at over three billion years in age. Yet they represent fairly advanced and complex organisms. What was life like before them from what did they evolve. Today a man can ask his questions a little differently than the Indian in the canyon did man knows now that the environment of the primitive earth was very different from today's environment. With sophisticated equipment he seeks to recreate in the laboratory the primitive conditions under which life might have begun in one nine hundred fifty three Stanley Miller conducting an experiment designed by Harold Yuri found new evidence of primitive evolution in a mixture of gases resembling the primitive atmosphere energized by electrical discharges he synthesised or amino acids. Fundamental constituents of protein which most living tissue is made. Other scientists like zero upon Emperor I'm a working with different chemicals and energy sources have also synthesize some of the building blocks of life. The synthesis of molecules in the primitive environment could have been the first step in the evolution of life. In the flasks scientists have produced a primordial soup. The evidence mounts that the first life might have evolved from non-living matter in just such an environment the next steps in the theory of organic evolution are more speculative the early organic molecules may have evolved from the Nama Gannicus soup into more complex molecules until one or more of them was able to reproduce itself and so begin the process of biological evolution. How did life begin. Room. Many men believe that life was created by a supernatural being. Yet man search for a scientific answer to this question is challenge his imagination and his skill through the ages is seen living creatures rise from non-living environments and suggested that life came from mom living matter. And he has looked at the skies and wondered if life came from elsewhere in the universe. Is look closely at living species. Room and. At fossils. Room. And at the earth. Repentance theorize that life evolved in the course of chemical changes in the Earth's primitive environment. Room. Man goes into the future with more knowledge and more skill than he had ever possessed before. As he begins to explore new planets perhaps you will find on them clues to the riddle of life on Earth. As his knowledge and experience expand. He may also find new ways to test is their ease and perhaps he will find new answers not even imagined today. Room. A.
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